Xevious is a vertically-scrolling shooter originally released in the arcades. It is notable for being the first game of that type to feature an aircraft flying over the Earth (as opposed to the outer space in other games), displaying views of South American nature. It also introduced, for the first time, two types of enemies to fight: aerial and ground-based (the menacing SOL towers invoked by GAMP to aid their planes). The player-controlled ship, Solvalou, is equipped with two weapons, each assigned to a button: the Zapper for air enemies, and the Blaster, which drops bombs on ground targets with the aid of a lock-on. The aerial enemies are divided into sub-categories distinguished by their attack and behavior patterns. Certain enemy types are immune to Solvalou's weapons, and must be avoided.